211221010011001 has 4 divisors (see below), whose sum is σ = 211223941794432. Its totient is φ = 211218078227572.

The previous prime is 211221010010981. The next prime is 211221010011023. The reversal of 211221010011001 is 100110010122112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 211221010011001 - 2⁷ = 211221010010873 is a prime.

It is a super-2 number, since 2×211221010011001² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211221010011031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1465783645 + ... + 1465927738.

It is an arithmetic number, because the mean of its divisors is an integer number (52805985448608).

Almost surely, 2^{211221010011001} is an apocalyptic number.

It is an amenable number.

211221010011001 is a deficient number, since it is larger than the sum of its proper divisors (2931783431).

211221010011001 is an equidigital number, since it uses as much as digits as its factorization.

211221010011001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2931783430.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 211221010011001 its reverse (100110010122112), we get a palindrome (311331020133113).

The spelling of 211221010011001 in words is "two hundred eleven trillion, two hundred twenty-one billion, ten million, eleven thousand, one".